Skip the auto shop - Our mechanics make house calls

Q: Thermostat reading high, car hard to start

asked by on

My car will give me problems when trying to start it. Sometimes it will turn on without a problem. On other occasions I would have to sit in the car for about 15-20 minutes before the engine actually comes on. Today, while driving, I noticed the thermostat reading was high, it was all the way up in the red zone. When I opened the hood the engine was very hot. About 2 days ago the engine was smoking a little but I didn't notice any changes in the thermostat. I towed it to a shop and they ran some test and said everything is fine but I'm here still wondering why the car won't start without a problem and why is my thermostat reading so high.
My car has an automatic transmission.

A: Hi, thanks for writing in. There are a few ...

Hi, thanks for writing in. There are a few reasons why this may happen such as a faulty or stuck thermostat, coolant fan switches that are not working or potentially a blown head gasket. I recommend checking the coolant to see if you find any traces of oil in it. Also, try checking the oil to see if you find any traces of water in it. If either of those are true, then you may have a blown head gasket.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Hear noise on driver's side wheel when turning right

The first clicking sound is likely coming from a faulty CV axle. This clicking sound is made by a faulty joint within the cv axle. I would first recommend having a suspension and brakes inspection performed by a qualified professional....

Q: Can an open gas cap which causes the Check Engine Light to come on cause the car to not start and the ECM to appear bad?

Yes, there are a lot of things a bad gas cap or open gas cap can affect. If you don't have a gas cap then you may be experiencing issues with debris getting into your tank or fuel filter and...

Q: Window motor broken

If your window motor is not engaging, it is likely that the motor has gone bad. It is also possible that the switch has gone bad, unless the window also rolls down, which would indicate that the switch is likely...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...